Aspects of the present disclosure are related to handling of data traffic in relation to a network controller—sideband interface (NC-SI). In a computer or other network connected device (e.g. switches, routers, and network controllers) a baseboard management controller (“BMC”) is a service processor or a microcontroller usually embedded on the motherboard of a server. The microcontroller uses sensors to report on matters such as temperature and fan speeds. The microcontroller may also control the operation of the system, including matters such as firmware updates, hardware configuration, power management, and monitoring. BMCs deployed in large network systems must be remotely accessible over the network, in particular via the network interface controller (“NC”) of the managed device, or via a serial port connected to the microcontroller. An Intelligent Platform Management Interface (“IPMI”) can specify a set of interfaces, protocols, and hardware buses for building such remote managed systems.
In such a network environment, the interface between the BMC and the NC can be referred to as the Network Controller—Sideband Interface (NC-SI). The NC-SI is a standardized interface that enables an NC to provide network access for a BMC, while allowing the NC to simultaneously and transparently provide network access for a host system. An NC-SI specification can define protocols and electrical specifications for a common Sideband Interface (SI) between a BMC and an 802.3 Local Area Network (LAN) via one or more external NCs. The NC-SI specification version 1.0.0 was published in July 2009 by the PMCI Working Group of the Distributed Management Task Force (DMTF).